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Sycorax follows a distant orbit, more than 20 times further from Uranus than the furthest regular moon, Oberon.[1] Its orbit is retrograde, moderately inclined and eccentric. The orbital parameters suggest that it may belong, together with Setebos and Prospero, to the same dynamic cluster, suggesting common origin.[8]

The diagram illustrates the orbital parameters of the retrograde irregular satellites of Uranus (in polar co-ordinates) with the eccentricity of the orbits represented by the segments extending from the pericentre to the apocentre.

The diameter of Sycorax is estimated at 150 km (assuming an albedo of 0.04),[4][5] making it the largest irregular satellite of Uranus, comparable in size with Puck and with Himalia, the biggest irregular satellite of Jupiter.

Sycorax is hypothesized to be a captured object: it did not form in the accretionary disk, which existed around Uranus just after its formation. The exact capture mechanism is not known, but capturing a moon requires the dissipation of energy. The possible capture processes include: gas drag in the protoplanetary disk, many-body interactions and the capture during the fast growth of the Uranus's mass (so called pull-down).[10][6]